Thermoplastic resins have versatile utility and are used, for example, as packaging material film. The processing of the thermoplastic resin into a film is typically conducted by melt-kneading thermoplastic resin mixed with a certain phosphorous antioxidant, and an anti-blocking agent to prevent thermal oxidation of the thermoplastic resin and blocking of the formed films.
JP2003-253061A discloses at paragraphs 34 and 37 to 50 a composition containing polyethylene resin, a phosphorous antioxidant, a hindered amine light stabilizer having at least one triazine ring, and anti-blocking agents such as aluminosilicate and kaolin.
It is also disclosed in JP4-220443A a polyolefin resin suitably used for films containing 0.01 to 3.0 parts by weight of an inorganic anti-blocking agent having surface —OH groups in the amount of 200 μmol or less per g of the anti-blocking agent as measured by the method of using triethyl aluminum disclosed in paragraphs 7 to 8 of the document, and 0.01 to 0.3 part by weight of aliphatic acid amide where the measurement of the surface —OH group was conducted by the steps of charging in a 100 ml flask 2 g of a sample of the anti-blocking agent, which had been dried in a desiccators under vacuum at 120° C. for 2 hours and then left standing and cooled to room temperature, adding 40 ml of dehydrated toluene thereto, replacing the atmosphere of the flask with dry nitrogen gas, adding 11 vol % triethyl aluminium solution in toluene under stirring thereto, measuring the amount of ethane gas produced by the reaction with the surface —OH group of the anti-blocking agent and tiethyl aluminium, and the calculation was made according to the following equation:n′=P′V/RTWwherein n′ represents the number of surface —OH group (mol/g), P′ represents pressure(atm), V represents the amount of evolved ethane (l: liter), R represents gas constant(atm·l/mol·° K), T represents ° K, and W represents the weight amount of the sample (g).